The very first Angel was discovered in Antarctica during the Katsuragi expedition lead by Misato's father. It was there that the first Angel, Adam, was found, described by those few survivors of the expedition team as a glowing giant. Humanity had found their god of gods, but when humanity attempted to contain what they had found, by reducing Adam to his embryo form, their god fought back, the second impact... Adam vanished, and was not seen again until many years later when humanity revived their god, from his remains found after the second impact, containing him in his embryo form. Then came the Angels.
Presumably Adam possesses similar abilities to the Evangelions constructed by both NERV and SEELE as the Eva series was created from Adam. In line with this presumption then, Adam most likely possesses superior strength over that of all the other Angels along with the ability to rapidly regenerate making the Angel the ultimate close combat opponent. As with all the other Angels, Adam possesses an S2 engine capable of providing an infinite source of energy, and it is rumoured that Adam has the ability to manipulate this energy in many devastating ways which would nicely explain the melting of Antarctica. Adam also possesses an AT, Absolute Terror, field, that is a kind of almost impenetrable force field, like all the other Angels, though its effectiveness is unknown.
Designated number: 2nd
First appearance: Episode 15
Presumably the second Angel is Lilith, the Angel held by NERV deep within terminal Dogma and mistaken by Misato and Kaji for Adam. Little is known about Lilith and where she came from, however, the seventeenth Angel, Kaoru, refers to humans as lilims, implying that Lilith is humanity's mother. The room Lilith resides in deep within terminal Dogma is actually NERV's LCL, Link Connection Liquid, manufacturing plant, it is here that Lilith hangs nailed to a large scarlet cross with the lance of Longinus buried within her chest preventing growth to the lower part of her body. NERV collect the blood that flows from Lilith's body and use it as LCL, this is picked up on by Shinji who frequently comments on the fact that an Eva's entry plug smells of blood.
Lilith is also the key to the human instrumentality project and the third impact. Apparently Lilith is capable of instigating the third impact and so is therefore invaluable to both Gendo and SEELE, however, Unit 01 is equally as valuable being built from Lilith, and hence effectively a viable substitute for Lilith should the need arise.
Designated number: 3rd
First appearance: Episode 01
Sachiel is the first Angel to assault Tokyo-3 following the destruction of Adam, though it's fifteen years after the second impact before Sachiel attacks the city. Why the long wait is a mystery, though its been rumoured that the Angels laid dormant on Earth until the second impact which some how awoke them from their dormancy. Like the Angels to follow, Sachiel challenges NERV alone, there would appear to be no systematic organisation amongst the Angels.
Sachiel is extremely well suited to the role of assaulting the enemy being equipped to despatch of both long range and close combat opponents. Sachiel's armament includes that of two ramming devices built into the palm of both hands, capable of delivering an incredible amount of pressure, and some kind of launcher mechanism used for projecting a type of high yield energy projectile with an unprecedented blast radius across long distances. This aside, however, Sachiel's AT field isn't as powerful as those exhibited by many of the other Angels, and the Angel's agility is mediocre at best, though Sachiel's extraordinary strength, ability to skim across surfaces and powers of regeneration more than makes up for this.
Designated number: 4th
First appearance: Episode 03
Only three weeks after the devastation caused by Sachiel, the Angels' follow up their attack on Tokyo-3 with their next messenger of death, Shamshel. Shamshel is solely suited to the role of close combat, and as a result of this is equipped with two what can only be described as laser tentacles, and it's these tentacles that Shamshel uses to savagely dissect opponents with. Shamshel's tentacles are so powerful that they can even manage to penetrate cleanly through the torso of an Eva, despite the protection provided by an Eva's defensive armour. Other than these awesomely powerful laser tentacles, Shamshel carries no further armament, though the Angel is capable of skimming across surfaces in much the same way as Sachiel. On the downside, however, Shamshel's AT field is as bad as Sachiel's, though the chance of an opponent scoring any hits on the Angel what with Shamshel's lethal tentacles flying around is slim.
Designated number: 5th
First appearance: Episode 05
Ramiel is by far one of the more powerful Angels to be pitted against the awesome might of the Eva series. Ramiel's armament consists of a drilling or boring device, which the Angel uses to attack NERV directly, and an exceptional AT field, so powerful in fact that the spatial changes in phase generated by the field can be seen by the naked eye. As if this weren't enough, Ramiel is also capable of skimming across surfaces and possesses a devastating accelerated particle beam cannon capable of shooting right through an Eva given roughly five seconds. Ramiel also indiscriminately targets opponents that enter within a set distance of the Angel, thus all in all Ramiel is a flying fortress capable of decimating those foolish enough to approach.
Designated number: 6th
First appearance: Episode 08
Gaghiel is the only aquatic Angel to be pitted against NERV and, unlike most of the other Angels, is relatively lightly armed. Gaghiel's armament consists solely of a set of huge razor sharp teeth that are used to tear apart opponents, Gaghiel's jaw is so powerful that the Angel can quite easily bite right the way through the torso of an Eva. Gaghiel is also massive, and as a result of this can use its immense size and weight to serve as potentially devastating weapons during close combat. Despite the Angel's size, Gaghiel is extremely agile and fast which is vital to the Angel as it has no means of which to engage opponents at long range, and so therefore relies on its speed and agility to rapidly engage the enemy in close combat. Gaghiel also possesses an AT field like all the other Angels, though its effectiveness is unknown.
Designated number: 7th
First appearance: Episode 09
Israfel is the first Angel to be engaged by two Evas simultaneously and, due to the damage incurred to Tokyo-3's intercept system, is also the first to be intercepted by NERV as opposed to the UN and/or JSDF. Despite being attacked by both Units 01 and 02, Israfel manages to dispatch of both its opponents due to the Angel's unique ability to separate into two separate Angels. Besides this bizarre ability to separate its self, Israfel also possesses some kind of offensive laser weapon, though its destructive power is somewhat lacking compared to the destructive arsenals at the disposal of most of the other Angels. Israfel's AT field is also extremely poor, however, the Angel is fairly agile and also possesses a set of razor sharp claws, and is hence therefore well suited to close quarter assault.
Designated number: 8th
First appearance: Episode 10
Sandalphon is not all that dissimilar to Gaghiel, though is capable of surviving extremely hot temperatures, what with the Angel's natural habitat being within an active volcano, as opposed to Gaghiel. Sandalphon is also a lot smaller in comparison, however, this is most likely due to the fact that Sandalphon is discovered by NERV during its infancy and so isn't fully developed at the time of the Angel's discovery. Sandalphon relies on its speed and agility to rapidly engage the enemy in close combat, much like Gaghiel, as the Angel possesses no means of which to engage opponents at long range. Sandalphon's only means of attack comes from its razor sharp teeth set into the Angel's powerful jaw, though this is more than enough to inflict extensive damage on any of the Angel's opponents. Sandalphon also possesses an AT field like all the other Angels, though its effectiveness is unknown.
Designated number: 9th
First appearance: Episode 11
Matariel is possibly one of the weakest Angels to attack Tokyo-3, and also the first Angel to be attacked by Units 00, 01 and 02 simultaneously. Matariel has only one means of attack being that of projecting extremely corrosive acid towards its opponents, however, this form of attack is slow and coupled with the Angel's limited agility makes for a pretty ineffective weapon. Matariel also possesses an extremely weak AT field which is not even capable of standing up to a short volley of fire from an Eva's standard issue rifle. These weaknesses serve only to hamper Matariel in combat and so the Angel relies chronically on its ability to stealthily approach opponents unnoticed, thus gaining the element of surprise giving the Angel the upper hand in combat.
Designated number: 10th
First appearance: Episode 12
Sahaqiel differs massively from the other Angels in that the Angel's one and only weapon is in fact its self. Sahaqiel is effectively a huge living bomb capable of dropping small amounts of its self, from the Angel's orbital position outside the enemy's firing range, on to targets below with devastating consequences. Though this may seem like an odd, yet extremely effective, way of dispatching of the Angel's opponents, Sahaqiel actually uses this unique ability to gain an absolute lock on its target, after which Sahaqiel descends on to its target thus eliminating not only its self, but also its target, along with a sizeable portion of the surrounding area! Sahaqiel has the potential to be truly devastating, which is why Sahaqiel's AT field is reasonably strong thus preventing the possibility of taking out the Angel at long range before delivery of its apocalyptic payload.
Designated number: 11th
First appearance: Episode 13
Ireul is almost the perfect Angel, or rather collection of Angels. Ireul is composed of colonies of nano machines which work together to form a single functioning intelligent circuit capable of adapting to any environment or situation it may encounter, thus Ireul's survival mechanism is that of total adaptability through continual evolution hence making the Angel an almost invulnerable opponent. Ireul possesses no armament, however, as the Angel is effectively an organic super computer, Ireul is quite capable of hacking into computer systems thus causing acts of sabotage. Ireul is also capable of merging with matter thus allowing the Angel to merge with its opponents attacking from within, and like all the other Angels, Ireul possesses an AT field, though its effectiveness is unknown.
Designated number: 12th
First appearance: Episode 16
Leliel is definitely one of the more bizarre Angels that NERV find themselves pitted against. Leliel is six hundred and eighty meters in diameter with a thickness of three nanometers within which is an inverted AT field, the sphere projected above Leliel is in fact the Angel's shadow. More intriguing is the fact that within the Angel's AT field is an alternate dimension or another galaxy, describable purely by abstract mathematics, which makes up the Angel's body, and it is into this world that Leliel lures and traps its victims. Leliel expands silently beneath its opponents pulling them into its body and is quite capable of trapping an Eva indefinitely in this way, indeed Leliel could quite easily engulf an entire city should the need arise thus making the Angel a formidable opponent.
Designated number: 13th
First appearance: Episode 18
Bardiel exhibits similar properties to that of a parasite and hence is one of NERV's darkest fears come true, that is when the Angel invades Unit 03 taking over complete control of its host and trapping its pilot inside the Eva's entry plug. Obviously this unique ability allows the Angel to adopt all the characteristics of its host and so depending on the Angel's choice of host, Bardiel can quite easily prove to be an exceptional opponent. As Bardiel chooses to invade and take control of Unit 03, NERV find themselves battling against the very same tool with which they intend to destroy the Angels, meaning NERV have to face off against one of their own defected living Avatars. Of course there's also a moral issue at stake, what with the pilot of Unit 03 trapped in side that which NERV intend to destroy.
Designated number: 14th
First appearance: Episode 19
Zeruel, at first glance, appears to be similar to Shamshel, though rather than being equipped with a set of laser tentacles, Zeruel possesses a set of cruel, lethal and flexible razor sharp blades which the Angel uses to slice apart its opponents. These blades are so devastating that they can even slice an Eva apart, this is also made doubly worse when considering their surprisingly long range. As if this weren't enough, Zeurel also possesses a kind of launcher mechanism used for projecting a type of high yield energy projectile in much the same way as Sachiel, though the effects from a single volley of fire from this weapon are truly devastating. To make matters even worse, Zeruel is capable of skimming across surfaces and has an impressive AT field making the Angel the ultimate assailant.
Designated number: 15th
First appearance: Episode 22
Arael is very similar to Sahaqiel in that Arael too is capable of maintaining an orbital position outside the enemy's firing range and possesses a single long ranged means of attack. Arael is capable of probing the minds of its victims forcing them to relive past memories best left forgotten, in effect Arael mentally rapes its opponents before eating away at their minds leaving them paralysed as a result of severe brain damage. As with Sahaqiel, Arael's AT field is reasonably strong thus preventing the possibility of taking out the Angel at long range, and so because of this Arael proves to be more than a challenge for NERV and their predominantly land based Eva series.
Designated number: 16th
First appearance: Episode 23
Armisael is undoubtedly the fastest, stealthiest, and most agile, Angel to confront NERV, in fact Armisael is so fast that the chances of an opponent actually hitting the Angel with ranged, or even close combat, attacks are slim. Armisael is also capable of altering its physical form, which further adds to the Angel's manoeuvrability, and has an impressive AT field which allows the Angel to easily rip through the defences of its opponents. As well as this, Armisael is capable of merging with its opponents attacking from within in much the same way as Ireul, though this is Armisael's sole means of attack and so the Angel relies on it's rapid manoeuvrability to engage the enemy in close combat.
Name: Tabris, aka Kaoru
Designated number: 17th
First appearance: Episode 24
Tabris, unlike any of the other Angels, is human in appearance and hence is able to infiltrate NERV unnoticed which is vital as Tabris possesses little in the way of offensive capabilities. Although Tabris's armament is limited, the Angel does, however, possess the ability to synchronise with an Evangelion both directly and remotely with ease, and at any desired synchronisation ratio provided that the Angel's soul is more dominant than that of the Eva's. This ability allows Tabris to take control of the very same tool with which NERV intend to destroy the Angel. Besides this unique ability, Tabris is also capable of generating an exceptionally strong AT field.